Light source



FIG. 1 is a perspective view of a light source showing my new design;

FIG. 2 is a side view thereof;

FIG. 3 is an end view thereof;

FIG. 4 is a top view thereof; and,

FIG. 5 is a perspective view of the light emitter element thereof.

The broken line showing of tips on the end is included for the purpose of illustrating only and forms no part of the claimed design. 

The ornamental design for a light source, as shown and described. 